Structural fracture development degree evaluation method and device, electronic equipment and storage medium

Abstract

The invention discloses a tectonic fracture development degree evaluation method and device, electronic equipment and a storage medium, and the method comprises the steps: obtaining the historical exploration information of each target well in a target region, and the historical exploration information comprises logging data, logging data and a data interpretation result; determining a target brittleness index ratio and a target rock stratum thickness value corresponding to the target area based on the historical exploration information; and determining a fracture development degree evaluation standard based on the target brittleness index ratio and the target rock stratum thickness value, and evaluating the tectonic fracture development degree based on the fracture development degree evaluation standard. Based on the above technical scheme, the evaluation parameters are determined based on the historical exploration information in the target area, and the evaluation standard of the fracture development degree is constructed based on the evaluation parameters, so that reasonable prediction and evaluation of the fracture development degree are realized based on the evaluation standard. The technical effect of improving the accuracy of predicting the development degree of the tectonic fracture is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploration and development, and in particular to a method, device, electronic equipment and storage medium for evaluating the development degree of structural fractures. Background Art

[0002] In oil and gas-bearing basins with developed compression anticlines, structural fractures are the natural fractures that have the greatest impact on the oil and gas seepage capacity of clastic reservoirs. Structural fractures are both high-speed seepage channels and oil and gas storage spaces, which can significantly improve the permeability of low-permeability and tight clastic reservoirs. Therefore, the prediction of structural fracture development intervals is of great significance to the exploration and development of tight clastic reservoirs.

[0003] However, in oil and gas-rich areas where compressional anticlines are developed, the core of the anticline is often located at a structural high, which is a favorable oil and gas-rich area. Therefore, it is often the deployment location of pre-exploration wells. For exploration wells that encounter the core of the compressional anticline, the distribution of structural fractures that can be detected in different layers in the vertical direction is not uniform, and it is difficult to accurately predict the development section of structural fractures in clastic rock formations without drilling coring and imaging logging. Summary of the invention

[0004] The present invention provides a method, device, electronic device and storage medium for evaluating the development degree of structural fractures. By constructing an evaluation standard according to the historical exploration information of the target area and reasonably predicting and evaluating the development degree of fractures based on the evaluation standard, the technical effect of improving the accuracy of predicting the development degree of structural fractures is achieved.

[0005] According to one aspect of the present invention, a method for evaluating the development degree of structural fractures is provided, the method comprising:

[0006] Acquire historical exploration information of each target well in the target area, wherein the historical exploration information includes well logging data, well logging data and data interpretation results;

[0007] Determining a target brittleness index ratio and a target rock layer thickness value corresponding to the target area based on the historical exploration information;

[0008] A fracture development degree evaluation standard is determined based on the target brittleness index ratio and the target rock layer thickness value, and the structural fracture development degree is evaluated based on the fracture development degree evaluation standard.

[0009] According to another aspect of the present invention, a device for evaluating the development degree of structural fractures is provided, the device comprising:

[0010] An information acquisition module is used to acquire historical exploration information of each target well in the target area, wherein the historical exploration information includes logging data, well logging data and data interpretation results;

[0011] A standard index determination module, used to determine a target brittleness index ratio and a target rock layer thickness value corresponding to the target area based on the historical exploration information;

[0012] An evaluation module is used to determine a fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and to evaluate the structural fracture development degree based on the fracture development degree evaluation standard.

[0013] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0014] at least one processor; and

[0015] a memory communicatively connected to the at least one processor; wherein,

[0016] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the method for evaluating the degree of structural fracture development described in any embodiment of the present invention.

[0017] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method for evaluating the degree of structural fracture development described in any embodiment of the present invention when executed.

[0018] The technical solution of the embodiment of the present invention obtains the historical exploration information of each target well in the target area, wherein the historical exploration information includes logging data, well logging data and data interpretation results, and determines the target brittleness index ratio and target rock layer thickness value corresponding to the target area based on the historical exploration information, and then determines the fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and finally evaluates the structural fracture development degree based on the fracture development degree evaluation standard. Based on the above technical solution, by determining the evaluation parameters based on the historical exploration information in the target area, and constructing the fracture development degree evaluation standard based on the evaluation parameters, and then realizing the reasonable prediction and evaluation of the fracture development degree based on the evaluation standard, the technical effect of improving the accuracy of predicting the development degree of structural fractures is achieved.

[0019] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 It is a schematic flow chart of a method for evaluating the development degree of structural fractures provided by an embodiment of the present invention;

[0022] Figure 2 It is a flow chart of a method for evaluating the development degree of structural fractures provided by an embodiment of the present invention;

[0023] Figure 3 is a cross-plot of the brittleness index ratio and the dimensionless average line density provided by an embodiment of the present invention;

[0024] Figure 4 It is a cross plot of the thickness of a single rock layer and the dimensionless line density of a single rock layer provided by an embodiment of the present invention;

[0025] Figure 5 It is a structural block diagram of a device for evaluating the development degree of structural fractures provided by an embodiment of the present invention;

[0026] Figure 6 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] Embodiment 1

[0030] Figure 1 It is a flow chart of a method for evaluating the degree of structural fracture development provided by an embodiment of the present invention. This embodiment can be applied to determining evaluation parameters according to historical exploration information of a target area, constructing a fracture development degree evaluation standard, and evaluating the degree of structural fracture development based on the evaluation standard. The method can be executed by a structural fracture development degree evaluation device, which can be implemented in the form of hardware and / or software. The structural fracture development degree evaluation device can be configured in an electronic device, which can be a terminal device or a server device, etc.

[0031] like Figure 1 As shown, the method includes:

[0032] S110, obtaining historical exploration information of each target well in the target area.

[0033] Among them, the target area can be a research area within the same structural belt selected according to research needs. Historical exploration information can be understood as historical information obtained after exploring the target area. Historical exploration information includes logging data, logging data and data interpretation results. Logging data can be logging information of each well in the target area, such as well number, etc. Logging data can be understood as logging data of each well in the target area, such as gamma logging data, sonic logging data, density logging data, etc. The interpretation result can be the result obtained after analysis based on the logging information, for example, it can be the formation data corresponding to the current well determined based on the logging data.

[0034] Specifically, the historical exploration information of each target well in the target area is obtained. For example, the researchers may select the exploration area to be studied as the target area according to the needs, and obtain the historical exploration information of each target well in the target area. The wells that meet the preset conditions may be selected from all the wells in the target area as the target wells. Alternatively, all the wells in the target area may be taken as target wells. The logging data of the target well may be obtained, and the historical exploration information corresponding to the target well may be extracted from the database based on the logging data. For example, the historical exploration information corresponding to the number of the target well may be obtained from the database based on the number of the target well.

[0035] On the basis of the above technical solution, the acquisition of historical exploration information of each target well in the target area includes: acquiring the geological fold type of each well to be selected in the target area; determining at least one target well in the target area based on the address fold type and the preset fold type, and acquiring the historical exploration information corresponding to the target well based on the preset depth interval.

[0036] Among them, the wells to be selected can be understood as all wells in the target area. The geological fold type can be understood as the type information of geological folds, which can include compression anticlines and synclines. Compression anticline structure refers to anticlines mainly formed by the compression of lateral pressure. Generally, the rock formations on both wings are steeper, with larger dip angles, often asymmetric, and often accompanied by reverse faults. The preset fold type can be understood as the pre-set fold type for screening target wells, which can be a compression anticline. The preset depth interval can be pre-set depth information, based on which the exploration information of the target well in the depth interval is obtained.

[0037] Specifically, the geological fold type of each well to be selected in the target area is obtained, at least one target well in the target area is determined based on the address fold type and the preset fold type, and the historical exploration information corresponding to the target well is obtained based on the preset depth interval. For example, the address fold type of each well to be selected in the target area may be obtained, and at least one target well may be determined based on the address fold type and the preset fold type. The well to be selected whose geological fold type matches the preset fold type may be taken as the target well, and the historical exploration information of the target well in the preset depth area is obtained based on the preset depth area.

[0038] S120. Determine a target brittleness index ratio and a target rock layer thickness value corresponding to the target area based on the historical exploration information.

[0039] The target brittleness index ratio may be a brittleness index evaluation standard for evaluating the degree of fracture development. The target rock formation thickness may be a rock formation thickness evaluation standard parameter for evaluating the degree of fracture development.

[0040] Specifically, the target brittleness index ratio and the target rock thickness value corresponding to the target area are determined based on the historical exploration information. For example, the geological parameters associated with the target area can be obtained by analyzing the historical exploration information, and then the target brittleness index ratio and the target rock thickness value corresponding to the target area are determined based on the geological parameters and used as evaluation parameters.

[0041] On the basis of the above technical solution, the target brittleness index ratio corresponding to the target area is determined based on the historical exploration information, including: determining the dynamic Poisson's ratio and dynamic Young's modulus of the rock corresponding to each target well based on the historical exploration information; determining the target brittleness index ratio corresponding to the target area based on the dynamic Poisson's ratio of the rock and the dynamic Young's modulus.

[0042] Among them, the dynamic Poisson's ratio of rock can be a parameter that describes the relationship between the two deformations of rock when it is subjected to compression force, i.e., compression deformation in a direction perpendicular to the compression force and tensile deformation in a direction parallel to the compression force. The dynamic Young's modulus can be an indicator used to measure the elastic deformation capacity of rock, which can reflect the degree of deformation of rock under certain stress.

[0043] Specifically, the dynamic Poisson's ratio and dynamic Young's modulus of the rock corresponding to each target well are determined based on the historical exploration information, and the target brittleness index ratio corresponding to the target area is determined based on the dynamic Poisson's ratio and the dynamic Young's modulus of the rock. For example, the dynamic Poisson's ratio of the rock can be obtained based on the density and acoustic wave data in conventional well logging. The dynamic Poisson's ratio can be obtained by Calculate and get, where μ d is the dynamic Poisson's ratio of rock, v p and v s They are the longitudinal wave velocity and the shear wave velocity in acoustic logging; the dynamic Young's modulus can be obtained by Calculated, where E d is the dynamic style modulus, v p and v s are the longitudinal wave velocity and the shear wave velocity in acoustic logging, respectively; ρ is the rock density obtained by density logging. It should be noted that in the process of collecting logging data, the logging instructions are collected based on the preset depth step, for example, data is collected every 0.125 meters, so the logging data at different depths need to calculate the corresponding rock dynamic Poisson's ratio and dynamic Young's modulus.

[0044] On the basis of the above technical solution, the brittleness index ratio corresponding to the target area is determined based on the dynamic Poisson's ratio of the rock and the dynamic Young's modulus, including: normalizing the dynamic Poisson's ratio of the rock and the dynamic Young's modulus to determine the normalized value; determining the brittleness index based on the normalized value, and determining the target brittleness index ratio based on the brittleness index and the historical exploration information.

[0045] Among them, the normalized value can be understood as the value obtained by normalizing the dynamic Poisson's ratio and dynamic Young's modulus of the rock. It should be noted that the normalized values ​​corresponding to the dynamic Poisson's ratio and dynamic Young's modulus of the rock are different. The brittleness index can be understood as the brittleness index corresponding to each depth value of the current target, which is used to evaluate the brittleness index of the formation at the current depth.

[0046] Specifically, the rock dynamic Poisson's ratio and the dynamic Young's modulus are normalized to determine a normalized value, and a brittleness index is determined based on the normalized value, and then the target brittleness index ratio is determined based on the brittleness index and the historical exploration information. The normalized dynamic Young's modulus at the current depth can be calculated by Calculate the normalized dynamic Poisson's ratio at the current depth, where (E d ) n and (μ d ) n are the normalized values ​​of dynamic Young's modulus and dynamic Poisson's ratio, E dmax ,μ dmax ,E dmin and μ dmin are the maximum and minimum values ​​of these two parameters, which can be 60 GPa, 0.43, 10 GPa, and 0, respectively. They are obtained based on the data statistics of the target layer in the study area, that is, the data obtained based on the statistics of historical exploration information, and then the brittleness index is obtained based on the normalized dynamic Young's modulus and the normalized dynamic Poisson's ratio. Among them, BI d is the brittleness index.

[0047] On the basis of the above technical solution, the method of determining the target brittleness index ratio based on the brittleness index and the historical exploration information includes: dividing the target well into formations based on the brittleness index to determine the ductile formations and brittle formations corresponding to the target well; determining the top brittleness index ratio based on the ductile formations and the brittle formations, and determining the target brittleness index ratio based on the top brittleness index ratio and the historical exploration information.

[0048] The stratigraphic division can be based on the brittleness index to classify the stratigraphic layers of the target well. The ductile stratigraphic layer can be understood as a stratigraphic layer with a brittleness index greater than a preset threshold, and correspondingly, the brittle stratigraphic layer can be understood as a stratigraphic layer with a brittleness index less than a preset threshold. The top brittleness index ratio is the brittleness index ratio of the target brittle layer to the adjacent ductile layer above.

[0049] Specifically, the target well is divided into stratigraphic layers based on the brittleness index, and the ductile stratigraphic layers and brittle stratigraphic layers corresponding to the target well are determined. Then, the top brittleness index ratio is determined based on the ductile stratigraphic layers and the brittle stratigraphic layers, and the target brittleness index ratio is determined based on the top brittleness index ratio and the historical exploration information. It should be noted that the brittleness index ratio of the brittle layer is d Higher, while the BI of the toughness layer d The brittle layer is mainly composed of sandstone, but also a small amount of brittle mudstone. The ductile layer is mainly composed of fine-grained mudstone, including a small amount of argillaceous sandstone or gravelly sandstone. The main basis of this division scheme is not BI d It is not the absolute value, but the relative size of its value, emphasizing the difference in rock mechanical properties between the target brittle layer and the adjacent ductile layer. Taking a single well as an example, at a shallow depth of 4800m to 4900m, the limit of the rock brittleness index is about 0.41. The value greater than this is basically a brittle layer, and vice versa. In the depth range of 4900m to 5000m, the limit of the brittleness index is about 0.48, that is to say, the brittleness index thresholds corresponding to different depths are different. It is necessary to determine the brittleness index threshold that matches the depth range based on historical exploration information, and then complete the division of the formation. Finally, determine the ratio of the brittleness index of the brittle layer to the brittleness index of the adjacent ductile layer. The brittleness index of a rock formation is the average value of the brittleness index of the corresponding depth section of the rock formation. The BI of the brittle layer and the ductile layers above and below it. d The ratio can be divided into top ratio RBI dntop and bottom ratio RBI dnbot Two types, respectively expressed as: Among them, BI dn is the average brittleness index of the target brittle layer; BI dntop and B.I. dnbot are the average brittleness index of the ductile layer above and below the target brittle layer, respectively.

[0050] On the basis of the above technical solution, the method of determining the target brittleness index ratio based on the top brittleness index ratio and the historical exploration information includes: determining the dimensionless average line density based on the historical exploration information, and determining the brittleness index cross-plot based on the dimensionless average line density and the top brittleness index ratio; determining the intersection brittleness index value based on the brittleness index cross-plot and a preset average line density value, and determining the target brittleness index ratio based on the intersection brittleness index value.

[0051] The dimensionless average line density can be obtained by dimensionless processing of the average line density. The average line density can be data obtained by statistics based on historical exploration information. The brittleness index cross plot can be understood as a cross plot for determining the target brittleness index ratio. It should be noted that the cross plot method refers to a mapping interpretation technology for well logging data, which intersects two types of well logging data on a plane map and determines the value or range of the desired parameter based on the coordinates of the intersection point.

[0052] Specifically, the dimensionless average linear density is determined based on the historical exploration information, and the brittle index cross-plot is determined based on the dimensionless average linear density and the top brittle index ratio, the intersection brittle index value is determined based on the brittle index cross-plot and the preset average linear density value, and the target brittle index ratio is determined based on the intersection brittle index value. It can be that within each brittle rock layer with developed fractures that has been divided, a layer segment of a single lithology with developed fractures is selected, and the sum of the number of fractures in these layers and the sum of the thickness of these layers are respectively counted according to the structural fracture data identified in the imaging logging interpretation results, and then the total number of fractures is divided by the total thickness of these layers to obtain the average linear density of the brittle layer, and then the dimensionless average linear density can be obtained by dividing the average linear density of the brittle rock layer by the arithmetic mean of the average linear density of all brittle rock layers in the target layer of the well, and then the dimensionless average linear density can be obtained, and then the dimensionless average fracture linear density and the top brittle index ratio (BI) are plotted. dntop ), determine the brittleness index value of the intersection point based on the brittleness index cross-plot and the preset average line density value, and determine the target brittleness index ratio based on the brittleness index value of the intersection point. The average value can be calculated based on the brittleness index of the intersection points on both sides, and the average value can be used as the target brittleness index ratio.

[0053] On the basis of the above technical solution, the target rock layer thickness value corresponding to the target area is determined based on the historical exploration information, including: determining the dimensionless fracture line density and the rock layer thickness under a single rock layer based on the historical exploration information; determining a rock layer thickness intersection diagram based on the dimensionless fracture line density and the rock layer thickness, and determining the target rock layer thickness value based on a preset line density value and the rock layer thickness intersection diagram.

[0054] The single rock layer may be a specific position in a stratigraphic sequence, or may be a rock layer with the same lithology. The dimensionless fracture line density may be line density data obtained by dimensionless processing of the fracture line density. The fracture line density may be understood as data obtained by statistical processing of historical exploration information. The preset line density value may be a preset line density threshold.

[0055] Specifically, the dimensionless fracture line density and the thickness of the rock formation under the single rock formation are determined based on the historical exploration information, and then the rock formation thickness intersection diagram is determined based on the dimensionless fracture line density and the rock formation thickness, and the target rock formation thickness value is determined based on the preset line density value and the rock formation thickness intersection diagram. It should be noted that, according to the single well lithology column diagram determined by cuttings logging and conventional logging, the depth and thickness of a single rock formation with the same lithology can be identified, and the depth of the single rock formation can be found on the imaging logging data and the number of fractures inside it can be counted. The fracture line density of the single rock formation can be obtained by dividing the number of fractures by the rock formation thickness. The dimensionless line density of the single rock formation can be obtained by dividing the line density of the single rock formation by the arithmetic mean of the line densities of all single rock formations in the target layer of the well, and then the rock formation thickness intersection diagram is determined based on the dimensionless fracture line density and the rock formation thickness, and the target rock formation thickness value is determined based on the preset line density value and the rock formation thickness intersection diagram.

[0056] S130. Determine a fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and evaluate the structural fracture development degree based on the fracture development degree evaluation standard.

[0057] The fracture development degree evaluation standard can be understood as standard data used to evaluate the fracture development degree.

[0058] Specifically, the evaluation standard for the degree of fracture development is determined based on the target brittleness index ratio and the target rock layer thickness value, and the degree of structural fracture development is evaluated based on the evaluation standard for the degree of fracture development. The evaluation standard for the degree of fracture development is determined by taking the target brittleness index ratio of 1.18 and the target rock layer thickness value of 1.4 as an example, as shown in Table 1.

[0059] Table 1

[0060]

[0061] For example, for brittle layers with a top brittleness index ratio greater than or equal to 1.18, the rock layers with an internal thickness of less than or equal to 1.4m tend to have a larger fracture line density, which is a location with relatively developed fractures; for brittle layers with a top brittleness index ratio less than 1.18 or a single rock layer with a thickness greater than 1.4m, the fracture line density is often small, and the fractures are generally underdeveloped. For wells that have not been cored and imaged in the study area, the degree of fracture development at the core of the anticline can be reasonably predicted based on the above-established standards.

[0062] The technical solution of the embodiment of the present invention obtains the historical exploration information of each target well in the target area, wherein the historical exploration information includes logging data, well logging data and data interpretation results, and determines the target brittleness index ratio and target rock layer thickness value corresponding to the target area based on the historical exploration information, and then determines the fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and finally evaluates the structural fracture development degree based on the fracture development degree evaluation standard. Based on the above technical solution, by determining the evaluation parameters based on the historical exploration information in the target area, and constructing the fracture development degree evaluation standard based on the evaluation parameters, and then realizing the reasonable prediction and evaluation of the fracture development degree based on the evaluation standard, the technical effect of improving the accuracy of predicting the development degree of structural fractures is achieved.

[0063] Embodiment 2

[0064] Figure 2 A flowchart of a method for evaluating the development degree of structural fractures provided in an embodiment of the present invention. Based on the above embodiment, this embodiment further optimizes the above method for evaluating the development degree of structural fractures. The specific implementation method can refer to the technical solution of this embodiment. Among them, the technical terms that are the same or corresponding to the above embodiment are not repeated here.

[0065] like Figure 2 As shown, the method of the embodiment of the present invention includes:

[0066] Obtain historical exploration information: Specifically, select wells with complete data that encounter the core of the anticline in the same structural compression zone, and collect as much geological data of the target layer as possible, including core and lithology logging data, conventional logging data and interpretation results, imaging logging data and interpretation results, etc.

[0067] Determine the brittleness index ratio based on historical exploration information: Specifically, the dynamic Poisson's ratio of the rock is obtained based on the density and acoustic wave data in conventional logging. The dynamic Poisson's ratio can be obtained by Calculate and get, where μ d is the dynamic Poisson's ratio of rock, v p and v s They are the longitudinal wave velocity and the shear wave velocity in acoustic logging; the dynamic Young's modulus can be obtained by Calculated, where E d is the dynamic style modulus, v p and v sare the longitudinal wave velocity and the shear wave velocity in acoustic logging respectively; ρ is the rock density obtained by density logging. It should be noted that in the process of collecting logging data, the logging instructions are collected based on the preset depth step, for example, data is collected every 0.125 meters, so the logging data at different depths need to calculate the corresponding rock dynamic Poisson's ratio and dynamic Young's modulus. The normalized dynamic Young's modulus at the current depth can be calculated by Calculate the normalized dynamic Poisson's ratio at the current depth, where (E d ) n and (μ d ) n are the normalized values ​​of dynamic Young's modulus and dynamic Poisson's ratio, E dmax ,μ dmax ,E dmin and μ dmin are the maximum and minimum values ​​of these two parameters, which can be 60 GPa, 0.43, 10 GPa, and 0, respectively. They are obtained based on the data statistics of the target layer in the study area, that is, the data obtained based on the statistics of historical exploration information, and then the brittleness index is obtained based on the normalized dynamic Young's modulus and the normalized dynamic Poisson's ratio. Among them, BI d It is the brittleness index. The strata are divided based on the brittleness index. The BI of the brittle layer d Higher, while the BI of the toughness layer d The brittle layer is mainly composed of sandstone, but also a small amount of brittle mudstone. The ductile layer is mainly composed of fine-grained mudstone, including a small amount of argillaceous sandstone or gravelly sandstone. The main basis of this division scheme is not BI d It is not the absolute value, but the relative size of its value, emphasizing the difference in rock mechanical properties between the target brittle layer and the adjacent ductile layer. Taking a single well as an example, at a shallow depth of 4800m to 4900m, the limit of the rock brittleness index is about 0.41. The value greater than this is basically a brittle layer, and vice versa. In the depth range of 4900m to 5000m, the limit of the brittleness index is about 0.48, that is to say, the brittleness index thresholds corresponding to different depths are different. It is necessary to determine the brittleness index threshold that matches the depth range based on historical exploration information, and then complete the division of the formation. Finally, determine the ratio of the brittleness index of the brittle layer to the brittleness index of the adjacent ductile layer. The brittleness index of a rock formation is the average value of the brittleness index of the corresponding depth section of the rock formation. The BI of the brittle layer and the ductile layers above and below it. d The ratio can be divided into top ratio RBI dntop and bottom ratio RBI dnbot Two types, respectively expressed as: Among them, BI dnis the average brittleness index of the target brittle layer; BI dntop and B.I. dnbot are the average brittleness index of the ductile layers adjacent to the upper and lower parts of the target brittle layer, respectively.

[0068] Determine the target brittleness index ratio: Specifically, within each brittle rock layer with developed fractures, select a single lithology segment with developed fractures, and count the sum of the number of fractures in these segments and the sum of the thickness of these segments according to the structural fracture data identified in the imaging logging interpretation results, and then divide the total number of fractures by the total thickness of these segments to obtain the average linear density of the brittle layer. The dimensionless average linear density can be obtained by dividing the average linear density of the brittle rock layer by the arithmetic mean of the average linear density of all brittle rock layers in the target layer of the well.

[0069] The cross plots of dimensionless average crack line density and top brittleness index ratio (BIdntop) and bottom brittleness index ratio (BIdnbot) are plotted respectively, as shown in Figure 3 As shown, it can be found that the degree of fracture development and the top brittleness index ratio (BIdntop) show a good positive correlation. We select the value of dimensionless average line density of 1 as a boundary, where a value greater than 1 indicates that the degree of fracture development in the brittle layer is higher than the average level of the well section; a value less than 1 indicates that the degree of fracture development in the brittle layer is lower than the average level. In the intersection diagram, the top brittleness index ratio corresponding to the intersection of the left envelope of the data point and the line with a line density value of 1 is about 1.09, and the intersection of the right envelope and it is about 1.27. The average value of BIdntop of the two intersection points is about 1.18, which is a relatively important boundary: brittle layers with BIdntop greater than this value often have more structural fractures, while brittle layers with BIdntop less than this value often have lower fracture density.

[0070] Determine the target rock formation thickness value: Specifically, based on the single well lithology column chart determined by cuttings logging and conventional logging, the depth and thickness of a single rock formation with the same lithology can be identified. Find the depth of the single rock formation on the imaging logging data and count the number of fractures inside it. Divide the number of fractures by the thickness of the rock formation to get the fracture line density of the single rock formation. Then, divide the single rock formation line density by the arithmetic mean of all single rock formation line densities in the target layer of the well to get the dimensionless line density of the single rock formation. Based on this, select the data corresponding to the rock formation with the number of fractures greater than or equal to 2, and draw an intersection diagram of the dimensionless line density of the single rock formation and the rock formation thickness, such as Figure 4As shown in the figure, the density of crack lines gradually decreases with the increase of rock layer thickness. The corresponding trend line and fitting formula are obtained by regression analysis of the scattered data in the figure. According to the fitted formula, we can obtain the rock layer thickness value corresponding to the dimensionless line density of 1, which is about 1.4m. It can be seen that when the thickness of a single rock layer exceeds 1.4m, the structural cracks are relatively developed.

[0071] Determine the evaluation standard for the development degree of structural fractures in the core of the compression anticline: Specifically, the top brittle index ratio limit of the brittle (rock) layer and the thickness limit of a single rock layer in the brittle layer can be used to establish a single well evaluation and prediction standard for the development position of vertical fractures in the core of the compression anticline in a strong structural compression area. For brittle layers with a top brittle index ratio greater than or equal to 1.18, the rock layers with an internal thickness of less than or equal to 1.4m often have a large fracture line density, which is a location with relatively developed fractures; for brittle layers with a top brittle index ratio less than 1.18 or a single rock layer with a thickness greater than 1.4m, the fracture line density is often small, and the fractures are generally underdeveloped. For wells that have not been cored and imaged in the study area, the degree of fracture development in the core of the anticline can be reasonably predicted based on the above-established standards.

[0072] The technical solution of the embodiment of the present invention obtains the historical exploration information of each target well in the target area, wherein the historical exploration information includes logging data, well logging data and data interpretation results, and determines the target brittleness index ratio and target rock layer thickness value corresponding to the target area based on the historical exploration information, and then determines the fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and finally evaluates the structural fracture development degree based on the fracture development degree evaluation standard. Based on the above technical solution, by determining the evaluation parameters based on the historical exploration information in the target area, and constructing the fracture development degree evaluation standard based on the evaluation parameters, and then realizing the reasonable prediction and evaluation of the fracture development degree based on the evaluation standard, the technical effect of improving the accuracy of predicting the development degree of structural fractures is achieved.

[0073] Embodiment 3

[0074] Figure 5 This is a structural block diagram of a device for evaluating the development degree of structural fractures provided by an embodiment of the present invention. Figure 5 As shown, the device includes: an image processing module 510 , a defect detection module 520 and a defect prompt module 530 .

[0075] The information acquisition module 510 is used to acquire the historical exploration information of each target well in the target area, wherein the historical exploration information includes logging data, well logging data and data interpretation results;

[0076] A standard index determination module 520 is used to determine a target brittleness index ratio and a target rock layer thickness value corresponding to the target area based on the historical exploration information;

[0077] The evaluation module 530 is used to determine the fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and evaluate the structural fracture development degree based on the fracture development degree evaluation standard.

[0078] Based on the above technical solution, the information acquisition module is used to obtain the geological fold type of each well to be selected in the target area; determine at least one target well in the target area based on the address fold type and the preset fold type, and obtain historical exploration information corresponding to the target well based on a preset depth interval.

[0079] On the basis of the above technical solution, the standard index determination module is used to determine the dynamic Poisson's ratio and dynamic Young's modulus of the rock corresponding to each target well based on the historical exploration data; and to determine the target brittleness index ratio corresponding to the target area based on the dynamic Poisson's ratio of the rock and the dynamic Young's modulus.

[0080] On the basis of the above technical solution, the standard index determination module is used to normalize the dynamic Poisson's ratio and the dynamic Young's modulus of the rock to determine the normalized value; determine the brittleness index based on the normalized value, and determine the target brittleness index ratio based on the brittleness index and the historical exploration information.

[0081] On the basis of the above technical solution, the standard index determination module is used to perform stratigraphic division on the target well based on the brittleness index, and determine the ductile formation and brittle formation corresponding to the target well; determine the top brittleness index ratio based on the ductile formation and the brittle formation, and determine the target brittleness index ratio based on the top brittleness index ratio and the historical exploration information; wherein the top brittleness index ratio is the brittleness index ratio of the target brittle layer to the adjacent ductile layer above.

[0082] On the basis of the above technical solution, the standard index determination module is used to determine the dimensionless average line density based on the historical exploration information, and determine the brittleness index cross-plot based on the dimensionless average line density and the top brittleness index ratio; determine the intersection brittleness index value based on the brittleness index cross-plot and the preset average line density value, and determine the target brittleness index ratio based on the intersection brittleness index value.

[0083] On the basis of the above technical solution, the standard indicator determination module is used to determine the dimensionless fracture line density and rock layer thickness under a single rock layer based on the historical exploration information; determine the rock layer thickness intersection diagram based on the dimensionless fracture line density and the rock layer thickness, and determine the target rock layer thickness value based on the preset line density value and the rock layer thickness intersection diagram.

[0084] The technical solution of the embodiment of the present invention obtains the historical exploration information of each target well in the target area, wherein the historical exploration information includes logging data, well logging data and data interpretation results, and determines the target brittleness index ratio and target rock layer thickness value corresponding to the target area based on the historical exploration information, and then determines the fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and finally evaluates the structural fracture development degree based on the fracture development degree evaluation standard. Based on the above technical solution, by determining the evaluation parameters based on the historical exploration information in the target area, and constructing the fracture development degree evaluation standard based on the evaluation parameters, and then realizing the reasonable prediction and evaluation of the fracture development degree based on the evaluation standard, the technical effect of improving the accuracy of predicting the development degree of structural fractures is achieved.

[0085] The device for evaluating the degree of development of structural fractures provided in the embodiment of the present invention can execute the method for evaluating the degree of development of structural fractures provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0086] Embodiment 4

[0087] Figure 6 A schematic diagram of the structure of an electronic device 10 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0088] like Figure 6As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0089] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0090] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a method for evaluating the degree of structural fracture development.

[0091] In some embodiments, the structural fracture development degree evaluation method can be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the structural fracture development degree evaluation method described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to execute the structural fracture development degree evaluation method in any other appropriate manner (for example, by means of firmware).

[0092] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0093] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0094] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0095] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0096] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0097] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0098] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0099] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for evaluating the development degree of structural fractures, characterized in that: include: Acquire historical exploration information of each target well in the target area, wherein the historical exploration information includes well logging data, well logging data and data interpretation results; Determining a target brittleness index ratio and a target rock layer thickness value corresponding to the target area based on the historical exploration information; A fracture development degree evaluation standard is determined based on the target brittleness index ratio and the target rock layer thickness value, and the structural fracture development degree is evaluated based on the fracture development degree evaluation standard.

2. The method according to claim 1, characterized in that Determining a target brittleness index ratio corresponding to the target area based on the historical exploration information includes: Determine the dynamic Poisson's ratio and dynamic Young's modulus of the rock corresponding to each target well based on the historical exploration data; A target brittleness index ratio corresponding to the target area is determined based on the dynamic Poisson's ratio of the rock and the dynamic Young's modulus.

3. The method according to claim 2, characterized in that The determining of the brittleness index ratio corresponding to the target area based on the dynamic Poisson's ratio of the rock and the dynamic Young's modulus comprises: Normalizing the dynamic Poisson's ratio and the dynamic Young's modulus of the rock to determine a normalized value; A brittleness index is determined based on the normalized value, and the target brittleness index ratio is determined based on the brittleness index and the historical exploration information.

4. The method according to claim 3, characterized in that: The determining the target brittleness index ratio based on the brittleness index and the historical exploration information comprises: Based on the brittleness index, the target well is divided into stratigraphic divisions to determine the ductile stratigraphic divisions and brittle stratigraphic divisions corresponding to the target well; A top brittleness index ratio is determined based on the ductile formation and the brittle formation, and a target brittleness index ratio is determined based on the top brittleness index ratio and the historical exploration information; wherein the top brittleness index ratio is the brittleness index ratio of the target brittle layer to the adjacent ductile layer above.

5. The method according to claim 4, characterized in that The determining the target brittleness index ratio based on the top brittleness index ratio and the historical exploration information comprises: Determining a dimensionless average linear density based on the historical exploration information, and determining a brittleness index cross plot based on the dimensionless average linear density and the top brittleness index ratio; The intersection brittleness index value is determined based on the brittleness index intersection diagram and a preset average line density value, and the target brittleness index ratio is determined based on the intersection brittleness index value.

6. The method according to claim 1, characterized in that Determining a target rock layer thickness value corresponding to the target area based on the historical exploration information includes: Determine the dimensionless fracture line density and rock layer thickness under a single rock layer based on the historical exploration information; A rock formation thickness cross-plot is determined based on the dimensionless fracture line density and the rock formation thickness, and the target rock formation thickness value is determined based on a preset line density value and the rock formation thickness cross-plot.

7. The method according to claim 1, characterized in that The acquisition of historical exploration information of each target well in the target area includes: Obtaining the geological fold type of each well to be selected in the target area; At least one target well in the target area is determined based on the address fold type and the preset fold type, and historical exploration information corresponding to the target well is acquired based on a preset depth interval.

8. A device for evaluating the development degree of structural fractures, characterized in that: include: An information acquisition module is used to acquire historical exploration information of each target well in the target area, wherein the historical exploration information includes logging data, well logging data and data interpretation results; A standard index determination module, used to determine a target brittleness index ratio and a target rock layer thickness value corresponding to the target area based on the historical exploration information; An evaluation module is used to determine a fracture development degree evaluation standard based on the target brittleness index ratio and the target rock layer thickness value, and to evaluate the structural fracture development degree based on the fracture development degree evaluation standard.

9. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the method for evaluating the degree of structural fracture development according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the structural fracture development degree evaluation method according to any one of claims 1 to 7 when executed.

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